The present invention relates to a controller provided with a touch detection device for performing touch detection responsive to depressing operation on a push-button type operating member (or operator), such as a remote controller suited for music production using a computer. The present invention also relates to a touch detection device constructed to perform touch detection in response to a movable contact pattern contacting a fixed contact pattern formed on a printed circuit board.
Heretofore, it has been known to previously install, in a general-purpose computer, an application program for implementing a music production function (i.e., digital audio workstation program that will hereinafter be referred to as “DAW software”) and perform music production using the installed DAW software. In the music production using such DAW software, a user inputs or enters various commands and values of various parameters, by use of a display, mouse and keyboard provided in a PC (Personal Computer) as standard equipment, so that behavior of the DAW software can be controlled. It is also conventionally known to use a physical controller, dedicated to the DAW software, to control behavior of the DAW software. There have been known various types of physical controllers (in terms of form of operation), such as one which includes, as its primary operators, fader operators and rotary knob operators and one which includes a keyboard as its primary operator (operating member). Generally, in many cases, such physical controllers include push-button type operators in addition to the aforementioned primary operators. In such cases, the push-button type operators are used exclusively as an ON/OFF switch and increment/decrement switch.
Also known is a physical controller provided with a pad type operator. The pad type operator is suited for entry operation of a rhythm part using a percussion instrument tone color because it can enter a MIDI velocity value or the like in accordance with an intensity level of user's hitting operation thereon. One example of touch detection devices for performing touch detection (pressing pressure detection) of various types of operators (operating members) including such a pad type operator is disclosed in Japanese Patent Publication No. HEI-02-49029 (hereinafter referred to as “patent literature 1”). The touch detection device disclosed in patent literature 1 includes two flexible support members opposed to and spaced from each other by a predetermined distance via a spacer member, and conductive patterns are formed on mutually-opposed surfaces of the two flexible support members. As the support members flex due to pressure (or load) acting on the surface of any of the support members, the conductive patterns contact each other so that a touch detection signal is output.
Further, as an example of a sensor capable of touch detection related to keyboard operation on an electronic keyboard instrument, a touch response sensor is disclosed in Japanese Utility Model Application Laid-open Publication No. SHO-52-101432 (hereinafter referred to as “patent literature 2”). The touch response sensor disclosed in patent literature 2 includes two generally rectangular, fixed contact sections parallel spaced from each other, and a resistant elastic or resilient member that contacts the fixed contact sections in response to key depressing operation. An area of contact between the resistant resilient member and the fixed contact sections is varied in response to a pressure increase of the key depressing operation, and resistance change responsive to variation in the area of contact between the fixed contact sections is detected.
In the touch detection device disclosed in patent literature 1, the mutually-opposed surfaces of the two flexible support members, opposed to and spaced from each other by the predetermined distance, are parallel to each other, and the conductive patterns are each formed in a straight shape on the corresponding surface. With such a construction, however, when the conductive patterns formed on the two flexible support members contact each other due to pressure (or load) acting on the surface of any of the support members, an amount of variation in the area of contact corresponding to the intensity of the pressure cannot be increased so much. Thus, a dynamic range of the touch detection signal output in response to operation of the operator is so small that the intensity of the operation of the operator cannot be detected precisely with a high accuracy.
Further, the touch response sensor disclosed in patent literature 2 is constructed in such a manner that the area of contact between the generally rectangular fixed contact sections and the resistant resilient member increases in one direction along the length of the fixed contact sections. With such a construction, a uniform detection value can be obtained in response to pressing or depressing force in the case of operation performed in one direction, such as key operation of a keyboard instrument. However, if the construction of the touch response sensor disclosed in patent literature 2 is applied to a push-button type operator, the detection value would become non-uniform due to an operated position and operated direction even in the case of depressing operation of same intensity, so that intensity of depressing operation cannot be detected accurately.
Further, with the conventionally-known physical controller of the DAW software, there has been a demand for performing parameter control using touch detection of a push-button type operator. However, the conventionally-known touch detection device would present the problem that the construction for performing the touch detection becomes relatively complicated, in addition to the aforementioned problem.
As another example of the touch detection device for keyboard operation on an electronic keyboard instrument, a sensor switch for a keyboard instrument is disclosed in Japanese Patent Application Laid-open Publication No. HEI-02-1832297 (hereinafter referred to as “patent literature 3”). The sensor switch for a keyboard instrument disclosed in patent literature 3 includes an upper substrate having flexibility and electrical insulating property, a lower substrate having an electrical insulating property and spaced from the lower surface of the upper substrate by a predetermined distance via a spacer member. Further, a conductive pattern (movable contact pattern) is formed on the lower surface of the upper substrate, and a felt cushion member is attached to the upper surface, which is a pressing surface, of the upper substrate. Further, an electrode section (i.e., electrode surface) is provided on a portion of the lower substrate's upper surface which is opposed to the above-mentioned conductive pattern. A contact section (switch contact) is constituted by the conductive pattern and the electrode section. Thus, as a pressing pounder is pressed by depression of a key of the keyboard, the upper substrate supported via the spacer is resiliently flexed downward so that the conductive pattern contacts the electrode section, and thus, the switch contact is turned on through electric conduction of the electrode section.
In the aforementioned construction, the conductive pattern is formed on the upper substrate by applying conductive paste onto the upper substrate, or by immersing the upper substrate, having its surface subjected to predetermined masking, in liquid conductive paint. In this case, the formed conductive pattern might differ, although slightly, in thickness dimension depending on various conditions, such as a temperature of the material and atmosphere at the time of the formation. Thus, the thickness dimension of the conductive pattern on the upper substrate cannot be completely the same per product of the sensor switch.
Further, with the construction disclosed in patent literature 3, the spaced-apart distance between the upper substrate having the conductive pattern formed thereon and the lower substrate having the electrode section formed thereon is determined by the thickness dimension of the spacer member. Thus, if the thickness dimension of the conductive pattern on the upper substrate differs per product as noted above, the spaced-apart distance between the conductive pattern and the electrode section would differ among products.
In such a case too, if the spaced-apart distance between the upper substrate and the lower substrate can be made great, namely, if a touch detecting stroke of a depressing member can be set greater, the thickness dimension of the conductive pattern can be made much smaller than the stroke, and thus, differences or variations in touch detection accuracy among different touch detection devices can be prevented from becoming very great.
By the way, in small-size switches or the like, the spaced-apart distance between the conductive pattern and the electrode section in a non-operating state of the switch is set very small. In this case, even if the thickness dimension of the conductive pattern differs only slightly, a great difference would occur in an output value (detection value) responsive to touch operation of same intensity. Namely, with a touch detection device having a small touch detecting stroke, it is difficult to realize a uniform touch detecting sensitivity among a multiplicity of products.
Among examples of touch detection devices like the one disclosed in patent literature 1 is one that is constructed to change luminance and displayed color of a display, disposed near the touch detection device, in accordance with intensity of user's operation to thereby allow the user to ascertain whether input touch operation of an intended intensity has been performed by the user. In this case, in order to allow the user to more intuitively identify or ascertain the intensity of the touch operation, it is desirable that a display be provided inside (within) of the touch detection device, e.g., immediately under the pad. However, with the sensor structure disclosed in patent literature 1, it is difficult to secure a space providing such a display inside the touch detection device, and thus, such a display has to be provided outside the touch detection device.